Azo dyestuffs containing heavy metal



AZO DYESTUFFS CONTAINING HEAVY METAL Guido Schetty andFabio Betta, Basel, Switzerland, as-

siguors to J. R. Geigy A. G., Basel, Switzerland, a

Swissfirm i i No Drawing. Application August 24, 1953 Serial No. 376,237

Claims priority, application Switzerland September 10, 1952 6 Claims. (Cl. 260-147) The present invention concerns the production of monoazo dyestuifs containing heavy metal which are excellently suited for the fast dyeing from a neutral to weakly acid dyebath of wool and of synthetic polypeptide fibres similar thereto such as nylon, Perlon or casein fibres. It is known that complex chromium compounds of metallizable monoazo dyestuffs which contain no acid Water solubilising groups such as sulphonic acid or carboxyl groups are very suitable for the fast dyeing of Wool and similar fibres insofar as they have sufficient water solubility for dyeing purposes. if certain hydrophilic substituents are not present in the dyestuff molecule, generallythe water solubility of such dyestuffs in insufiicient. A hydrophilic substituent which can be easily introdufced and is therefore often usedtis the sulphamide group -SO NH Its acid character however, is so prominent that it has an unfavourable influence on the drawing power on to wool from a neutral bath. Complex chromium compounds of azo dyestuffs which have no acid water solubilising groups and contain the sulphamide group as hydrophilic substituent can be seen, on dyeing wool, to need acid to a greater or lesser extent according to the constitution which prejudices their use in combination with other chromium-containing dyestufis.

The substitution of the sulphamide group by hydrocarbon United States Patent ice X represents a hydroxyl or carbonyl group standing in the o-position to the azo group or a substituent which can be converted into such a group under the conditions of the metallizing reaction,

R and R represents low molecular aliphatic or, if desired, also alicyclic hydrocarbon radicals, and

n represents 1 or 2,

and wherein the sulphamide groups are aromatically bound. The radicals A and B can be substituted as desired provided the substitution is non-ionogenic, e. g. by halogen, alkyl, alkoxy, aryloxy, nitroacylamino, alkylsulphonyl, arylsulphonyl, sulphonic acid dialkylamide, sulphonic acidaryl ester, carboxylic acid ester and carboxylic acid amide groups. They should not contain any acid water solubilizing groups however, apart from the radical A which may have a earboxyl group participating in the complex formation.

The complex heavy metal compounds correspond to the type (D-M D)M In this formula, D represents the monoazo dyestuif according to this invention, M

. represents a complexly bound cobalt or chromium atom radicals greatly reduces the hydrophilic action, whereby the acid character is only slightly influenced; in the twice substituted sulphamide group the acid character and also its hydrophilic properties are practically removed.

It has now been found that complex chromium and cobalt compounds of metallizable monoazo dyestuffs without acid groups, with the exception of a carboxyl group which may possibly be present participating in the complex metal linkage, are sutficiently water soluble and need only a very slight addition of acid when dyeing wool if there is at least one and, advantageously not more than two, sulphonic acid oxalkyl-alkylamide groupsas hydrophilic substituents in the dyestufi molecule, be it in the diazo or the coupling components.

The metal-containing dyestufis according to the present invention are obtained by treating with agents giving off chromium or cobalt, monoazo dyestuffs of the general formula:

wherein:

and M represents the equivalent of a cation, in particular that of an alkali metal or ammonium.

The unsulphonated diazo and coupling components usual in the production of chromium dyestuffs, if desired those containing the substituents listed above, can be used to form the monoazo dyestuffs usable according to the present invention. o-hydroxy, o-carboxyor o-alkoxyamino compounds of the benzene and naphthalene series can be used as diazo components; as coupling compo nents, those compounds of the aliphatic, aliphatic-aromat ic, aromatic-isocyclic or aromatic-heterocyclic series coupling in the o-position to a phenolic or enolic hydroxyl group are suitable, in particular acylacetic acid arylamide, phenols, naphthols, S-pyrazolones. At least one of the components of the azo dyestufi should contain a sulphonic acid oxalkyl-alkylamide group; this is easily done by converting sulphonic acid groups according to the usual methods into sulphonic acid halide groups and treating these with an excess of a secondary alkanolamine. It is preferable that the sulphamide group be derived from methylamino or ethylamino alkanols wherein the alkanol radical can contain 2-6 carbon atoms and it is advantageous if the hydroxyl and the amino group are bound to neighbouring carbon atoms. The sulphonic acid methylor ethyl-oxethyl-aniide groups are particularly valuable substituents.

Diazo components with a sulphamide group according to the present invention can be produced e. g. from 4-halogen 3 nitrobenzene-l-sulphochloride by reaction with methylor ethyl-amino ethanol, exchange of the halogen atom for the hydroxyl group by means of caustic alkalies and reduction of the nitro to the amino group. Coupling components with the sulphamide group according to the present invention are obtained, e. g. from 3- or 4-aminobenzene-l-sulphonic acid-methylor ethyloxalkylamide by reacting with acylacetic esters or diketene whereby acylacetic ester arylamides result, or by diazotizing the amino grou. reducing the diazo to the hydrazino group and condensing with acyl acetic esters to form 1aryl-5-pyrazolones. The coupling components can also be obtained from acyloxynaphthalene-sulphonic acid halides and alkylamino alkanols and saponification of the acyloxy to hydroxyl groups. The diazotization is performed with sodium nitrite as usual in the cold in mineral acid solution or suspension and the coupling is done in an alkaline solution. Yellow, orange, red, brown, violet, blue and grey dyestulfs can be produced which can be converted into the corresponding coloured heavy .metal complexes.

The metallization is performed advantageously in aqueharness ous solution or suspension at raised temperature by the action of salts of cobalt or of trivalent chromium. It is done in such a way that there is at least 1 atom of heavy metal to two dyestufi molecules. Preferably the alkali salts of chromosalicylic acid are used for chroming. The metallization can be performed open under reflux or in a closed vessel under pressure, if necessary with the addition of dispersing agents such as Turkey red oil. It can also be done in high boiling organic solvents and diluents, e. g. in formamid e, dimethyl formamide or in the urea melt. Temperatures of over 100 and the use of pressure are particularly recommended when any substituents in the o-position to the azo group such as alkoxy groups or halogen atoms are. to. be. replaced by the. hydroxyl group during the metallizing process.

The complex chromium or cobalt compounds of the monoazo dyestuffs defined above generally have suflicient water solubility for dyeing purposes. if necessary it can be improved, by mixing the, dyestufiis. with inorganic. salts having an. alkaline reaction such as sodium carbonate or trisodium phosphate or with organic anion: active wetting and dispersing agents such as, soap and. synthetic washing agents.

The new chromium or cobalt-containing dyestufiis dye Wool very evenly even from, a neutral toweakly acid bath, e. g. one containing; ammonium sulphate: and Glaubers salts, withveryv gQQd exhaustion. of. the dyebath. Due to, their similar behavioun on, dyeing; they canv be combined very wellor also. canbecombinedwitli other similar dyestuffs The following examplesillustrate the. invention. without;limiting; it. in any way.- Where notot-herwise stated, partsare given, as parts by weight and the temperatures are in degrees Centigrade. Therelationshipzof. parts by weightto; parts by volume is, as that. of kilogrammes. to litres.

Chromium complex.

24.6' parts of Z-amino-1-hydroxybenzene-4=sulplionic acid-N-methyl-hydroxyethylamide are dissolved in- 200 parts of'hot water with 17 parts ofconcentrated'hydroohloric acid, the solution is cooled to 5 anddiazotized :with a' solution of sodium nitrite (corresponding-"to 6J9 :parts); The diazonium suspension-is made neutral with sodium bicarbonate and poured into; a solution of' 21.9 parts of 'l'-(3'-chloro)-phenyl-3-methyl 5apyrazolone; 10.5 parts by volume of 10- N-caustic soda lye'and 12 parts of'anhydrous soda in 100 parts ofwater. On-"completion of the dyestutf formation, the dyestuifis'isolated at 70 by the addition of sodium chloride and, afterbeing pasted in 600 parts of hot water, is chromed by boiling with" 120- parts by volume of a solution ofammonium chromosalicylate (corresponding to 4.2 parts of chromic oxide) until thecomplex formation is complete; The chromium containing dyestuff is isolated'by filtering. After drying it is a brown-yellow powder which dyes wool from a neutral or weakly acid bath in very'fast, level orange shades.

If in the above example, the 1-'(3"-chlor o) phenyl=3-' methyl-S-pyrazolone isreplaced by'25.5 .partsof-1- 314'"- dichloro) -phenyl-3-methyl-5-pyrazol-one, a dyestuif having similar properties is obtained;

Z-amino-l-hydroxybenzene-4-sulphonic acid-Nnneth'yh hydroxyethylamide can be produced as follows:

1-chloro-2-nitrobenzene-4-sulphochloride is converted into the corresponding l-chloro 2 nitrobenzene-4-sulphonic acid-N-methyl-hydroxyethylamide by treatment with N-methyl-ethanolamine in an aqueous medium at a low temperature. This product is stirred at the boil for some hours with diluted caustic soda lye. The resulting Z-nitro l hydroxybenzene-4-sulphonie acid-N- methyl-hydroxyethylamide is reduced to the amino compound by the usual methods, e. g. by heating withsodiinh sulphide solution. (M. P. 177.)

Cbbalt' complex 48.8 parts of the dyestufi which is obtained according to Example 1 by diaz'otizing 2-amino-l-hydroxybenzene- 4-sulphonic acid-N-methyl hydroxyethylamide and coupling with 1-('3 chloro) phenyl-3-methyl 5-pyrazolone, is heated for 1 hour at 8-0 in 600' parts'of water with 60 parts of cobalt acetate (corresponding to 3.54 parts Co). Anhydrous soda is addedfuntil there is a phenolphthalein alkaline reaction ('11 parts) and the whole is stirred for another 5 hours at"85. Thecob'alt containingdye stuff is isolated by the addition of sodium chloride. After drying, the dyestufi'is' a brown powder which dyes wool from a neutr'alor'weakly acid bath in orangey'ellow shadesv which have very good wet fastness" and very high light fastness properties.

EXAMPLE 3 on NIL-CO 60H;

NH! HO SOn-TIT-CHaOHzOH' Chromium complet of chromic oxide) are added and the whole is boiled until the complex formation is complete. The chromium containing dyestuif is isolated by the addition of sodium chloride. After drying, it is a bluegrey powder which dyes wool from a neutral or a weakly acid bath in very fast, level blue grey shades.

If in the above example the 1-carbornethoxyamino-7- hydroxynaphthalene is replaced by 21.1 parts of l-acetylamino-7-hydroxynaphthalene or by"27.4' parts-"of" 7 hy= droxynaphthyl-(l) carbamic acid methoxy ethylTe'ster, dyestuifs with similar .propertie's'are obtained."

5 1 EXAMPLE 4 OH NH: OH

HI Chromium complex 24.6 parts of Z-amino-l-hydroxybenzene-4-sulphonic acid-N-methyl-hydroxyethylamide are diazotized as described in Example 1. The diazonium suspension is then neutralized with sodium bicarbonate and poured at -5 into a solution of 15.1 parts of 2-hydroxynaphthalene in 200 parts of water, 4.2 parts of sodium hydroxide and 15 parts of soda. After thedyestulf formation is complete the dyestulf is isolated by filtration. It is heated in 750 parts of hot water with 120 parts of a solution of ammonium chromosalicylate (corresponding to 4.2 parts of chromic oxide) and the whole is boiled until the complex formation is complete. The chromium containing dyestufi is isolated by the addition of sodium chloride, filtered, and dried. It is a violet black powder which dyes wool from a neutral or a weakly acid bath in fast, level violet shades.

EXAMPLE 5 N OH S0zNCHsCH:OH

Cobalt complex 24.6 parts of Z-amino-1-hydroxybenzene-4-sulphonic acid-N-methyl-hydroxyethylamide are diazotized according to Example 1 and coupled with Z-hydroxynaphthalene as described in Example 4. The dyestuff is isolated and then pasted in 750 parts of water at 80, parts by volume of 10 N-caustic soda lye and 60 parts of a cobalt acetate solution (corresponding to 3.54 parts of Co) are added and the whole is stirred for PA hours at 75-80. The cobalt containing dyestutf is precipitated by the addition of concentrated hydrochloric acid and filtered 01f. After drying, it is a dark brown powder which dyes wool from a neutral or weakly acid bath in wine red shades.

The dyeings have excellent fastness properties.

EXAMPLE 6 OH J OrN-CHgCHzOH Cobalt Complex 24.6 parts of Z-amino-1-phenol-4-sulphonic acid-N- methyl-hydroxyethylamide are diazotized as described in Example 1 and neutralised with sodium bicarbonate. The diazonium suspension is then poured into a solution of 18.6 parts of acetoacetic acid anilide, l0.5 parts by volume of 10 N-caustic soda lye and 12 parts of anhydrous soda in 100 parts of water. When the formation of the dyestufi is complete, the dyestufi is isolated at 70 by means of sodium chloride and, after being. pasted in 600parts of water with 60 parts of cobalt acetate solution (corresponding to 3.54 parts Co), it is metallized for 3 hours at 80-85 Sodium carbonate is added until there is a phenolphthalein alkaline reaction and the whole is heated for a .furlhet 3 hours at 80-85; The dyestutf Or-N-CHzCHs-OH SOz-N-CHzCHsOH H; i

Chromium complex 24.6 parts of Z-amino-1-hydroxybenzene-4-sulphonic acid-N-methyl-hydroxyethylamide are diazotised according to Example 1. The diazoniurn suspension is neutralized by the addition of sodium bicarbonate, afurther 3 parts of sodium bicarbonate are added and the whole is poured into a solution of 32.7 parts of l-phenyl-S-methyl- 5-pyrazolone-3'-sulphonic acid N methyl-hydroxyethylamide in parts of water and 10.5 parts by volume of 10 N-caustic soda lye. On completion of the dyestuff formation, the dyestuff is salted out and filtered oif. It is then pasted in 600 parts of water, parts of a solution of ammonium chromosalieylate (corresponding to 4.2 parts of chromic oxide) are added and the whole is boiled for some hours. After drying, the chromium complex which is isolated by means of sodium chloride, is a brown orange powder which dyes wool from a weakly acid bath in full very level orange shades. The dyeings have very good fastness properties.

. 1-phenyl-3-methyl5-pyrazolone-3'-sulphonic acidmethyl-hydroxyethylamide is produced as follows:

' m-Nitrobenzene sulphochloride is converted at 0-5" in an aqueous medium into the corresponding m-nitrobenzene sulphonic acid-N-methyl-hydroxyethylamide with N-rnethylethanolamine. The reduction of the nitro to the amino group and the conversion of the diazo compound into the corresponding hydrazine and the condensation to l-phenyl-3-methyl-5-pyrazolone-3'-su1phonic acid-N- methyl-hydroxyethylarnide are performed in the usual manner.

EXAMPLE 8 C Ha Chromium complex by volume of 10 N-caustic soda lye. On completion of the dyestutf formation, the 'dyestuff is isolated at 60 by the addition of sodium chloride, pasted in 600 parts of t re whi h dye we f w r, 1&9 par s at se i tiqn 9t anmpnium s amme- Chromium complex 27.4; parts of 2-.aminobenzoic acid-S-sulphonic acid-N- methyl-hydroxyethylamide are dissolved in 150 parts of water with 10.5 paritszbyvolume-of 10. N-caust-ic soda Lye, a solution of 6. 9- partsv of sodium nit-rite is added and, after cooling to 5*, the whole is v stirred into a mixture of. 30 parts of concentrated hydrochloricacid, 100 parts of water and 30 parts ofice. Sodium bicarbonate is added until there isa neutral reaction to congo red paper, a f urther b parts of sodium bicarbonate are added and the diazonium compound is then poured into a solution of 21.9 parts of l-('3'-ch-loro)ephenyl-il-methyl-5-pyrazolone, 10.5: parts by volume of 1 N-oaustic soda lye in partsof Water.

On completion of the dyestuif formation, the dyestuif is isolated by means of: sodium chloride and, a-fter'being pasted i-n600-par ts of hotwater, itis chromed-by boiling with 120 parts: of a solution ofammoniumchromosalicyl-ate (corresponding to 4.2 parts of chromic oxide) until the complex formation is complete. The chromium containing dyestutf is precipitated with sodium vchloride, filtered oflf and dried; After drying, it is an orange yellow powder which dyes woolfrom a neutral or weakly acid bath invery fast, level, yellow shades.

2 amino benzoic acid sulphonic acid -N-methylhydroxyethylamide is produced as follows:

2 chlorobenzoic acid 5 sulphochloride is stirred at 0l0- for some hours with N methylethanolamine, the resulting J @h1r h' b.i "a9 1;- -I Ste hani a dt ..Y t n n er ed: i to h Z-smir compound by treatment-in the autoclave under pressure at 160-180 with concentrated ammonia in the presence of copper powder and coppertsalts (M. P. 186.)

red owd erlwhichdye wooequat r. a e/ea in 2 amino 1 hydroxyben zene 5 sulphethyl-hydroxyethylamide is produced according to the information given for the production of 2 amino 1 '1 hydroxybenzene 4 lsulphomethyl-hydroxyethylamide (see Example 1) by replacement of the methylethanolainide by ethylethanolamide. (M. P. 170.)

wsor-n-ontc noa Chromium complex 14.4 parts of kehloroQ-aminod-phenol in parts of water and 17 parts of concentrated hydrochloric acid are diazotized at 015 with 20 parts by volume of 5 N- sodium nitrite solution, After neutralizing with sodium carbonate at 043' the diazonium suspension is poured into a solution of 29.5 parts of 1-nap'hthol-3asulphonic acid-Nemethylahydroxyethylamide, 10.5 parts by volume of 10 N-cau-stic soda lye and 300- parts of water. On completion of the dyestutf format-ion, sodium chloride is added, the dyestuir' is filtered oif, pasted in 800 parts of water, 200 parts by volume of a solution of ammonium chromosalicylate (corresponding to 7.6 parts of Cr O are added and the whole is boiled under reflux for 20 hours. The. chromium containing dyestuif: is precipitated by the addition of sodium. chloride, filtered ofi and dried. It is a blue-black powder which dyes wool from a neutral or Weaklyacid bath in navy blue shades,

1 naphthol 3 sulphonic acid. -N hydroxyethylmethylamide is produced as follows: le-naphthol-3-sulphonic acid; is estenified with toluene sulphochloride and af hor ugh drying s co ve ted.- w th pho nhorus p ntalQ t t s nf -to y naoh holfinlphoni c c lo de. is la he cond nsed wit me yleth o amine and t e Q L rasl eal s split o i'by eati g with. di u ed aus ic so a yr- LB (recrysta lized. fr m, d lu d. alcoho 13.4113 t EXAMPLE Chromium complex 14.4 parts of 4-chloro-2-amino-l-phenol are diazotized and after neutralizing with-sodium bicarbonate are poured at 15 intorasolutio'nof 29 .5 parts of 2-naphthol-6-sulphonic acid-N-hydroxyethylmethylamide, 4.4 parts of sodium hydroxide and 12 par-ts of anhydrous soda in 600 parts of water. The whole is then heated to 20 and stirred at this temperature until thecouplingis complete. 16 parts of sulphonated castor oil and parts by volume of a solutionofammonium chromosalicylate (coresnqnd etofihiivnailsCrzQal areadderd nd the Whole is bp il e d,for 3 ,ho der reflux. The mixture is cooled, to,95 20 =parts,of sod um chloride; are added, the whole sthoilesl o'rifnr her, aihou t andthen the-precipitated y stuff is. filtered ofi hot. After, drying, the dyestuff is a blue-violet powder. which dyes wool from a neutral bath n. slearrvi let hade hielltha eneryesppdtastn s p o ert1 The 'following' dyestaffs can be produced according to the information given in the above examples:

Table Colour of the No. Dlazo component Coupling component Metal metal complex on wool l -chloro-2-amlno-ll-phenyl-3-methyl-5- Cr scarlet.

phenol-4-sulphonic pyra zolone. acid-N-rnethylfilydroxy-ethylam- 2 4-methyl-2-amino-1- do Or Do.

,phenol-s-suli i phonic acid-N- methyl-hydroxyethylarnide.

3 .-do 1-(3'-chlorophenyl)- Co brownj ,olone. low.

4-c hloro-2-amino-1- l-phenyl-S-methyl- Or red. phenol-fi-sulli-pyrezolone.

phonic acid-N- methyl-hydroxyethylarnide.

5 2-amino-l-phenol-4- 3.4-dimethyl-1- Cr reddish sulphonic acid-N- phenol. brown. methyl-hydroxyethylamide.

6 4-n tro2-amino-l- 4-amyl-l-phenolnn. Cr brown.

phenol-ti-sulphonic acid-N-ethylhdydroxy-ethylam- 7 4-chloro-2-arnino-1- l-hydroxynaph- Cr reddish phenol. thalenel-sulviolet. phon c acid-N- methyl-hydroxyethylamide.

8 4-nltro-2-amino-1- do Cr Bordeaux phenol. red

9 S-nitro-Z-amino-ldo Or bluep en violet.

10 6-nitro-4-rnethyl-2- l-hydroxynaph- Or navy amino-l-phenol. thalene3-sulblue.

ph0n"c acid-N- methyl-hydroxyethylamide.

11 4-chloro-5-nitro-2- l-hydroxynaph- Cr greenish amino-l-phenol. thulene-fi-sulgrey.

phonic ecid-N- methyl-hydroxyethylemide.

12 4.6-dinitro-2-amino- Z-hydroxynaph- Or violet 1-pheno1. thalene-8-sulbrown.

phon c acid-N- m ethyl-hydroxyethylarnide.

13 2-amino-l-phenol-5- 1-(3-chlorophenyl)- Cr scarlet.

sulphonic acid-N- 3-methyl-5- methylhydroxypyrazolone. cthylamide.

14 4-chloro-2-amlno-1 2-hydroxynaph- Co ruby phenol. thalene-fi-sulred.

phonic acId-N- methyl-hydroxycthylamide.

15 6-nltro-4-methyl-2- 2-hydroxynaph- Cr grey.

amino-l-phenol. thalenet-sulphonic acid-N- methyl-hydroxyethylamido.

16 4-ohloro2-amlno-1- -do Cr reddish phenol. navy blue.

17 4.6-dlchloro-2- do Cr violetamino-l-phenol. A grey.

18 6-nitro-2-amlno-1- l-(3-sulphonic ac1d- Cr scarlet.

phenol. N-mcthyl-hydroxy ethylurnldophenyl)-3- methyl-5-pyrazclone.

19 anthranillcacid-. do Cr yellow.

20 5-nitro-2-amino-1- do Or blush phenol. red.

21 4-chloro-6-nitro-2- do Or red.

emino-l-phenol.

22 2-arnino-l benzo c l-(3.4-d chloro- Gr yellow.

acid-fi-sulph onic phenyl) -3-methylacld-N-m ethyln-pyrazolone. laydroxy-ethylarn- 23 2amino-1-pheno-4- 3-methoxy-4-methyl- Cr Borsulphon c aeid-N- l-phenol. deaux methyl-hydroxyred. ethylamide.

24 2-nrnino-l-phenol-4- 2-hydroxynaph- Cr reddsh sulphon e aed-N- alene-fi-sulviolet. dirnethylamide. phonc acid-N- m eth yl-hydroxyethylamide.

25 2-amino-l-phenol-5- l-carlrorrethoxy- Cr blush sulplonc acd-N- amino-7-hydroxygrty. n'et yl-hydroxynaphthalene. ethylarnidc.

wherein A represents a radical of the benzene series,

B represents the radical of a member selected from the group consisting of phenolic, naphtholic and pyrazolonic coupling components, containing the hydroxy group in ortho-position to the azo group,

X represents a metallizable group in o-position to the azo group selected from the group consisting of 0H and COOH,

R and R are lower alkyl radicals, in which R+R' contain not more than 8 carbon atoms, and

each of m and n is one of the numerals 0 and 1, m-l-n being at least 1.

2. A complex chromium compound of the formula:

[D-Cr-DlM wherein M is a cation and D is a co-ordinated monoazo dyestutf of the formula:

OH (|)H g l SOgN-CHrCHrOH 3. A complex cobalt compound of the formula:

[D-Co--D]M wherein M is a cation and D is a co-ordinated monoazo dyestuff of the formula:

SOr-N-CHrCHsOH 4. A complex chromium compound of the formula:

[DCr--D]M wherein M is a cation and D is a co-ordinated monoazo dyestufif of the formula:

OH OH SO: COOCH:

1 112 A complex cobalt compound of th tfp tmuli JA s nx l i e mmin :.Qmnm11 59 theifiwzmlm I, [,DHCDHDlM D -Cr-D]M wherein M is a cation and D is a co-ordinated monoazu wherein M is a cation and D is a cp-ordinatcd n onqqzg dyestuff of the formula: 5 dyestuff of the formula:

.Q.- .i f -v v N=NG\ I I 10 SOFNL-CEQBQOH C=N cm H: S'O: 3 1m 15 References Cited in the file ,o f this gamut 0H1 UNITED STATES PATENTS 2,391,180 McNalleyet a1 Dec. 18, 1945' 2,537,098 Slifkin et al. Jan. 9, 1951 2,606,185 Widmeiet a1.' Aug. 5, 1952 

1. A COMPLEX HEAVY METAL COMPOUND OF THE GENERAL FORMULA: 